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<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        // 3.concat

        var arr1 = [10,20,30];
        var arr2 = ['hello','nice'];

        var newArr = arr1.concat(arr2,arr1,true,false,66);
        console.log(Arr)



        // 4. slice
        var arr1 = [10,20,30,40,50,60];
        
        // splice
        
        
    </script>
</body>
</html>